HTPC The Home Entertainment PC – Part 4 Assembly

Why you should consider it: Short-Media digs up a few tricks and items to keep in mind for Section Four: Assembly. The HEPC is a smaller case and with that comes some tight squeezes. There is also noise to contend with and the last thing wanted is a PC drowning out high fidelity sound.

The HEPC (Home Entertainment PC)

The computer is finding its way into the living room. This invasion brings
about horrifying visions of trailing cables as the PC crawls out of the primordial
soup of the home office. How can the fledgling PC compete against a world otherwise
dominated by components that are chameleons hiding behind names like home theatre
and game boxes?

The PC is itself becoming more of a chameleon whether it hides behind the disguise
of office productivity or of home entertainment center. Can the powerful PC,
supreme in its native office environment, survive in the jungle of your living
room? Does it have to be an eyesore shooting off cables like vines growing wild?

Home Theatre PC or HTPC is a popular term. Home Theatre implies that the PC
will be used to play back DVD movie content with a PC rather than a stand alone
consumer grade player. The HTPC isn’t a “set-top box” either. A set-top
box is a device which enables a viewer to become interactive with the television
set. Set-top boxes may appear to be similar to PCs but they aren’t.

Why a PC in the living room?

We wouldn’t be recommending dragging the tower out of the home office to stand
it beside the TV. We wouldn’t want to scar the decor either with a bland, beige
box noisily whirring away. The thought of cables trailing across the floor gives
us hives.

PCs are more affordable these days. There used to be a time when it was one
TV per household. Now two or three is common. The same can be said for the PC
and with the sheer amount of digital content some are accumulating it only makes
sense to incorporate that into the home entertainment center for music, games
and movies.

The HEPC (He-PC…no pun intended) combines Home Theatre quality DVD playback,
high quality audio, gaming, Internet and all the creature comforts of a traditional
PC into a unit that blends in with the living room or family room environment.
The HEPC offers the ability and advantage of storing large volumes of digital
video and audio. It has the benefit of connecting with other PCs in the household.
There also need not be cables strung everywhere ready to snag limbs as you pass
by like catch wires on the deck of an aircraft carrier.

Assembling the HEPC isn’t complicated or expensive and the technology is surprisingly
good. In some cases it may be even better than what is presently sitting in
the home entertainment cabinet. In Section One we looked into PC case choices
featuring Lian Li and Coolermaster. Section two explored the latest technology
in Micro-ATX motherboards. Section three answered every question we could think
of about audio and presented a few facts you might not have known.

Short-Media digs up a few tricks and items to keep in mind for Section Four: Assembly.
The HEPC is a smaller case and with that comes some tight squeezes. There is
also noise to contend with and the last thing wanted is a PC drowning out high
fidelity sound.

These and more will be answered.

Section 4: Putting it all together

Assembly of the HEPC is no different from any other computer.
Devices are plugged in, ram is snapped in and an OS is installed. The HEPC resides
in a compact case and a few of the rules have to be broken. The example PC case
is the Coolermaster ATC-610-GX1 which was previously examined in depth.

The Chaintech 7NIF2 Micro-ATX motherboard isn’t the same size
as its ATX brethren. It is almost 3 inches shorter and those extra 3 inches
in a standard PC case do come in handy. Let’s begin with the finished assembly
and work backwards.

It all looks pretty tidy with the DVD drive on the left and hard
drive and floppy (hidden below the hard drive) on the right. The first tip is
cables. The rage is for rounded cables but these will be more of a nuisance
for the hard drive and floppy drive. Rounded ATA cables may provide for less
restrictions in airflow in a standard PC case but will loop all over the place
in a small case such as this. It will be like a garden hose laying all over
the driveway…no place for it to go. Standard flat ribbon cables can be folded
and tucked under the floppy drive to keep cables in their place.

You’ll note that one rounded cable was used to reach from the
motherboard IDE header to the DVD drive. The Coolermaster ATC-610-GX1 has a
crossbar running down the length of the case and cable tie (Zap strap) can be
used to secure the rounded cable to the crossbar to hold the rounded cable up
out of the way.

Choice of heatsink is important with the Coolermaster ATC-610-GX1
for two reasons; perimeter size and height.

From the socket to the underside of the crossbar is only a smidgen
over 4 inches. Any higher than 4 inches and the heatsink won’t fit. Also there
is airflow to contend with. Give as much space as possible between the inside
roof of the cowling and the top of the heatsink and that includes the fan. Leave
at least an inch.

The perimeter of the heatsink will present a problem if the heatsink
80mm. square. For the reason look at the overhead image.

Note that big black power supply sitting in the lower left corner.
There is only about 10mm. clearance between it and the 70x70mm. heatsink that
is in place. Choice of heatsink is up to the user but it would be highly recommended
to choose a quiet design heatsink that generates less than 30 dB(A) of sound.

Extra Cooling Ghetto Style

(Originally from part
4 of a five-part HTPC series.)

There is no point assembling a HTPC only to have it intrude on
the enjoyment like a cat yowling on the fence. To that end it was decided that
extra cooling was needed and that was to be provided by an old 31 CFM 28 dB(A)
80mm. fan. The question was where to put it and not have to drill holes in the
case. The ATC-610-GX1 has two vents either side just behind the front bezel
area.

The drive bays inside the case have a little more than 40mm. of
space between the drive bay and the inside wall of the case. A perfect fit for
a 25mm. fan. The object is to provide cool air intake assistance at the front
of the case that will be drawn out by the existing rear exhaust fan.

In the image above you can see the area where the fan has room
to be placed…but how. For this you have to look at the inside of the cowling
where the fan would be mounted.

The left side of the image is the edge of the cowling that slots
in directly behind the front bezel. Look to the right of the image would be
looking to the rear of the case.

So the fan must sit there but no screws are allowed plus the vibration
must be kept to a minimum. The SST-LC01 has a very nice finish to it and we
wanted to avoid drilling holes and mounting fan grills. It’s not as tough as
you think and it can work anywhere in any PC case.

Run out to the neighborhood hardware store and get two items that
should set you back less than $10. The first is Lepages Instabond #8. This is
super glue and it sticks most anything. The important fact is that it mustn’t
be caustic to rubber. In other words it shouldn’t dissolve petroleum based products.
(plastic, rubber, styrofoam).

Next is sponge rubber weather stripping.

This is a foam like strip that has a self-adhesive side. It is
5mm. thick by 10mm. wide. Larger widths are not needed. This weather stripping
is usually put around doors or windows and comes in a generous 17 foot coil.

You’ll need an 80mm. fan. Again don’t choose a howler. You want
to assist the airflow into the case not create a hurricane.

Cut two strips of the weather stripping 75mm. long.

Cut those strips lengthways to produce four 5mm. wide 75mm.
long strips.

Now run a bead along one edge of the fan frame. Make sure it is
the proper side. This is an intake fan so you want to run a bead of glue on
the “sucking” side. (Hint: look for the airflow direction arrow on
the side of the fan frame.)

Glue one side strip at a time and be careful as this glue will
stick to you and you then will stick semi-permanently to anything else. Glue
the NON-adhesive side of the weather stripping to the edge of the fan frame.
You’ll then end up with four strips adhesive side exposed.

After 10 minutes the glue has thoroughly set and the paper protecting
the self-adhesive face can be removed. The fan can then be “stuck”
to the inside of the case.

No screws are needed and it will remain stuck for a good long
time. (I’ve had one stuck to the side of bookcase for 3 months now….don’t
ask.) The weather stripping between the fan frame and the metal acts like a
shock absorber to the fan vibration.

A word about dampening

Fans vibrate and that vibration transfers. A fan that is solidly
bolted to a sheet of metal will transfer the fan vibration to the metal. The
metal may end up amplifying the sound. The fan vibration can be reduced by introducing
a cushioning material like the sponge weatherstrip. This acts the same way as
a shock absorber in a car. It “cushions” the ride and dampens the
sound.

To that end sound vibration can also be reduced by reducing a
materials ability to vibrate. The Coolermaster ATC-610-GX1 cowling is thin and
as such will not be an effective barrier to sound. VBLOCK
provided two answers.

VBLOCK is a tile-like substance that has a self adhesive backing.
It can be cut to size with a pair of scissors and is only 2mm. thick. It dampens
case vibration by providing structural reinforcement. That dampening of vibration
and partial blocking of sound aids in keeping fan noise in check.

Exhibit A: the empty cowling

Exhibit B: the VBLOCK applied.

The VBLOCK strengthens the metal panel thus reducing the amount
of vibration it can transfer and also changing the tonal quality of that sound
to a lower, less obtrusive level. Realize that all noise prevention linings
do not block sound but merely change the sound to a more tolerable level by
reducing its strength and vibration through the surroundings. It helps but not
to a great extent.

Obsessed with power

The Coolermaster ATC-610-GX1 and Lian Li PC9400 accommodate standard
ATX power supplies. There is no point in building the HEPC if it is noisy. The
Zalman ZM400A-APF provides ample power at, as the Zalman
site states, noiseless or silent levels. The ZM400A-APF is part of Zalman’s
CNPS (Computer Noise Prevention System) line of products. These are meant to
operate at a whisper…and they do.

The Zalman ZM400A-APF power supply does not look much different
from any other single fan power supply. It’s only when the housing is removed
that the large heatsinks are revealed.

These heatsinks dissipate a tremendous amount of thermal energy.
From 20-45 degrees Celsius the fan operates at around 20 dB(A) which is near
silent. It is only when the power supply senses an internal temperature over
56 degrees Celsius that the fan begins to increase fan speed generating approximately
30 dB(A). The sensor is shown in the next image.

Zalman includes a 4-pin molex to 3-pin molex adapter. The black
designate 12 volt and the white are 5 volt. The 80mm. side intake fan we installed
was plugged into the 5 volt line. This made the 80mm. fan spin at a much lower
RPM and also near silent. Be aware that all fans will not start spinning with
this low a voltage but a 7 volt mod can be done to reduce fan noise. The lower
RPM also means lower CFM but any cool air moving into a PC case is good air.

Also included are velcro strips to secure loose wiring. We suggest
you read Mediaman’s Tech Tips: Cleaning up the cables for a complete guide on
tidying up wires and cables in a PC case.

400 watts is more than enough power for the HEPC system but the
true advantage is the lack of noise. The Zalman ZM400A-APF is extremely quiet
and that’s just what you want in a power supply for the HEPC. The Zalman PSU
does have short cable lengths which may be a disadvantage in larger PC towers
but they are perfect for the HEPC. Cable organization is that much easier with
less cables to tuck away.

The Zalman power supplies are, without a doubt, the most silent
power supplies. While in silent mode your ear literally needs to be 2-3 inches
away to know if it is even running.

Quietly keeping your cool

Choosing a heatsink can be a challenge. The quest is for silence
balanced with cooling efficiency and it seems never shall the two meet. Keep
silence foremost in the mind. We’ve said it before and we’ll say it again. The
HEPC doesn’t “blend in” if it contains a howling fan.

Thermaltake
answered our call with the Volcano
11 Xaser Edition. Thermaltake told us it was a heatsink that could handle
it all for socket A right up to the latest Athlon XP 3200+. (3400+ listed on
the Thermaltake website.) The heatsink fan has manual, automatic and constant
speed control and can turn out from 20.55 CFM to a hurricane force of 75.7 CFM.

75.7 CFM at 48 dB. Yes that stopped us cold too…or did it? The
goal is quiet. The Volcano II only generates 17 dB at the lowest speed of 1300
RPM. That is extremely quiet. Therefore the happy medium had to be found.

The Thermaltake Volcano II Xaser Edition has two options for speed
control; automatic and manual. The automatic function utilizes a thermistor.

This thermistor can be affixed by the included thermal tape under
the CPU.

This was not the favorable choice since the range is 20 degrees
Celsius to 55 degrees Celsius corresponding to fan RPM; lowest to highest. The
processor chip most likely operates at a higher temperature and thus the fan
would spin faster to compensate. A section option was to insert the thermistor
into the fan fins to allow for the fan to automatically increase speed with
temperature but the range would be much lower since the fins would not be as
warm.

The third option was to utilize the PCI bracket rheostat for manual
control of fan RPM.

Temperature tests are for illustrative purposes only since this
is not a formal review of the Thermaltake Volcano II. The thermistor was placed
in the fins near the sink base for the automatic portion and the PCI slot rheostat
was used for manual control. Ambient room temperature was 24.6 degrees Celsius.

The automatic setting is something that a user can experiment
with by placing the thermistor on different points on the heatsink. Since the
heatsink itself won’t get as warm as the processor core the fan RPM will be
much lower. The fan will speed up as the heatsink warms up due to processor
activity.

We chose the manual setting to keep the RPM constant regardless
of activity. The HEPC will be inside a home entertainment unit cabinet and that
will also aid in suppressing noise. We settled on a very quiet 3000 RPM setting
which keeps the processor relatively cool at around 53 degrees Celsius.

Choosing a heatsink is ultimately up to the needs and preferences
of the user. Be aware of the height. Do not exceed approximately 3 inches from
base to top of the fan. There needs to be enough of a gap to maintain good airflow
into the heatsink fan mouth. The power supply will have to be removed prior
to installing any heatsink with the Chaintech 7NIF2.

There just isn’t the room between the power supply and the fan
in order to access the clip. There is no need to totally remove the power supply.
Only the mounting screws have to be removed in order to temporarily swing it
out of the way.

Remember that noise is the evil enemy in the HEPC. The manual
speed control of the Thermaltake
Volcano II Xaser Edition does allow for some adjustment between silence
and full-on cooling power. Search out heatsink reviews and if one catches your
eye; just make sure the fan operates below 30 dB(A) otherwise it may intrude
upon your listening enjoyment. The risk of cooling fan noise intruding increases
the more that you exceed 30 dB(A). Realize that the game, music or DVD audio
pumping through the home theater amplifier will drown out the fan noise in a
lot of situations…except for those quiet moments during a movie.

Assembling final thoughts

Assembling a Home Entertainment PC is no different from assembling
a normal PC but there are a few things to keep in mind. There are only four
PCI slots available. One will go to the sound card. One will go to the wireless
NIC. One will go to a PCI USB bracket and that leaves one remaining PCI slot.
The Chaintech 7NIF2 motherboard has 2 USB ports on the backplane and headers
for 4 more USB ports. That’s important when hooking up all the wireless toys
that will be featured in section five; cutting the cables.

The HEPC can be near silent….except when you turn up the stereo
and hear what was meant to be heard. Choose quiet components. Ensure the PC
case has adequate cooling or install additional low-noise, low-RPM fans. Plan
the installation an make use of cable ties to secure stray wires. Remember that
rounded cables may not be the most practical choice in cramped quarters.

Be sure to check out section one for PC case choices, section
two for motherboard pointers and section three for all that you ever need to
know about high quality PC audio.